But it can change the meaning. For instance, if I write a tweet that says "I like the joker character" and twitter appends my tweet saying "People that like joker might shoot up a movie theater", you've changed the intent and meaning completely from what was intended... The media tends to do this kind of thing a lot when they take a speech and add their own commentary to change what was said. Appending/elaborating on what someone says makes them your words, not the original authors.